133 Research report Occurrence of fluoride in groundwater of Zarand region, Iran 133 Fluoride 47(2)133–138 Derakhshani, Tavallaie, Raoof, Mohammadi, Abbasnejad, Haghdoost April-June 2014 OCCURRENCE OF FLUORIDE IN GROUNDWATER OF ZARAND REGION, KERMAN PROVINCE, IRAN Reza Derakhshani,a Morteza Tavallaie,b Maryam Raoof,c,g Tayebeh Malek Mohammadi,d Ahmad Abbasnejad,e Ali Akbar Haghdoostf Kerman, Iran SUMMARY: The fluoride (F) content and distribution pattern of groundwater, the main drinking water source, in 35 villages and towns in the Zarand area in Kerman Province of Iran were assessed using the F ion chromatography method. The average groundwater F concentration was 1.80 mg/L (range: 0.33–3.51 mg/L) and in 22 sites the F concentration exceeded 1.5 mg/L, the maximum F drinking water level recommended by the World Health Organization (WHO). Exposure to excess dietary F may lead to chronic disease with detrimental health effects, including dental and skeletal fluorosis, and providing safe water for domestic use is recommended. Keywords: Dental fluorosis; Distribution pattern; Drinking water; Groundwater; Iran. INTRODUCTION Globally, millions of people are affected by the serious problem of fluorosis which is correlated with a high concentration of F ion in drinking water.1-7 Although the average drinking water F concentration in Iran is relatively low, high levels occur is some areas.8-10 Groundwater is a major source of human intake of F, including its subsequent incorporation into food and beverage items. The excessive intake of F has a negative metabolic effect and may lead to various adverse health effects, both skeletal and non-skeletal, including dental fluorosis, skeletal fluorosis, and neurological complications.11-16 The amount of F in groundwater is considered to be a function of many factors such as solubility and availability of F minerals in rocks,17 composition of the host rock through which the groundwater has flowed, velocity of flowing water, pH, temperature, concentration of bicarbonate and calcium ions in water18 and characteristics of the aquifer.19, 20 Despite the importance of the subject, the study in Iran of groundwater F levels21-3 and the relationship between F levels and dental decay,29, 31 has been done in only a limited part of the country. In the only groundwater F study done in Zarand, an area in the Central Iran Zone notable for dental fluorosis, Poureslami et al.32 evaluated the groundwater F content only within the city of Zarand (30º48’46”N, 56º33’50’’E). In the present study we assessed groundwater F from villages and towns in a wider part of the Zarand area. aAssistant Professor, Department of Geology, Shahid Bahonar University, Kerman, Iran; bPhD student, Department of Dental Public Health, School of Dentistry, Kerman University of Medical Sciences, Kerman, Iran. cAssistant Professor, Department of Endodontics, School of Dentistry, Kerman University of Medical Sciences, Kerman, Iran. dAssistant Professor, Kerman Oral and Dental Diseases Research Center, Department of Dental Public Health, School of Dentistry, Kerman University of Medical Sciences, Kerman, Iran. eAssociate Professor, Department of Geology, Shahid Bahonar University, Kerman, Iran. fProfessor, Research Center for Modeling in Health, Institute of Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran. gAuthor for correspondence: Dr Maryam Raoof, Department of Endodontics, School of Dentistry, Kerman University of Medical Sciences, Kerman, Iran. E-mail: [email protected] 134 Research report Occurrence of fluoride in groundwater of Zarand region, Iran 134 Fluoride 47(2)133–138 Derakhshani, Tavallaie, Raoof, Mohammadi, Abbasnejad, Haghdoost April-June 2014 METHOD In 35 villages and towns in the Zarand district, groundwater samples were collected from drinking water sources and Qanats, elaborate tunnel systems used for extracting groundwater in dry mountain basins in a sustainable manner (Figure 1). Latitude and longitude are shown on the outside of the figure as Universal Transverse 3 Mercator (UTM) coordinates N 29 5 35 9 11 23 Geographic 33 32 27 25 6 coordinates for 28 Zarand 1 30º48’46”N 16 26 15 34 21 20 7 10 31 30 22 4 13 18 17 8 19 12 2 24 14 Region of Zarand Geographic coordinates for Zarand 56º33’50’’E Sampling points 0.34–0.5 F level in Contour lines 0.5–1 ground 1: Ab-pangueyeh; 2: Badiz; 3: Banan; 4: Chahkin; 5: Dasht water mg/L khac; 6: Deh-Shigh; 7: Dahuiyeh; 8: Bab-Haviz; 9: Bab- 1–1.5 Tangal; 10: Deh-Asgar; 11: Shabchareh; 12: 1.5–2 Gatruiyehgadid; 13: Deh-Milan; 14: Gatruiyehgadim; 15: Hosn Abad; 16: Hoosn; 17: Hamidiyeh; 18: Madboon; 19: 2–2.5 Gorgafk; 20: Motahar Abad; 21: Deh-Irag; 22: Khanuk; 23: 2.5–3 Sarbag; 24: Sabluiyeh; 25: Sirize; 26: Sang; 27: Sirize1; 28: Shahrokh Abad; 29: Rashc Sar; 30: Reyhan Shahr; 31: Tagi 3–3.5 Abad; 32: Yazdan Abad; 33: Yazdan Abad1; 34: Zarand; 35: 3.5–4 Fath Abad. 4–4.5 Figure 1. Drinking water F levels in the Zarand region. 135 Research report Occurrence of fluoride in groundwater of Zarand region, Iran 135 Fluoride 47(2)133–138 Derakhshani, Tavallaie, Raoof, Mohammadi, Abbasnejad, Haghdoost April-June 2014 Before sampling, the sampling containers, colorless polythene 1L plastic barrels, were dipped into nitric acid for 24 hr, washed with 10% HCl, made clean with tap water, and finally washed with distilled water. At the sampling site, the containers were flushed three times with the water being sampled before the sample was taken. The F content of the groundwater samples were determined by the F ion chromatography method.33 RESULTS AND DISCUSSION The groundwater was free from taste, odour and colour. The F concentrations in the groundwater of the 35 villages and towns of the Zarand region are shown in Table 1, Figure 1, and Figure 2. Table 1 . F level in the drinking water in the 35 villages and towns in the Zarand region Village or town F mg/L Village or town F mg/L Village or town F mg/L Ab-pangueyeh 3.13 Deh-Milan 1.87 Sirize 0.96 Badiz 1.19 Gatruiyehgadim 2.05 Sang 0.33 Banan 1.32 Hosn Abad 1.51 Sirize1 2.86 Chahkin 1.22 Hoosn 1.44 Shahrokh Abad 2.34 Dasht khac 1.62 Hamidiyeh 2.05 Rashc Sar 1.48 Deh-Shigh 1.7 Madboon 1.64 Reyhan Shahr 2.56 Dahuiyeh 3.05 Gorgafk 1.38 Shahrokh Abad 2.34 Bab-Haviz 1.32 Motahar Abad 3.51 Tagi Abad 1.63 Bab-Tangal 2.73 Deh-Irag 2.52 Yazdan Abad 1.94 Deh-Asgar 3.45 Khanuk 1.59 Yazdan Abad 1 0.39 Shabchareh 2.53 Sarbag 0.59 Zarand 0.53 Gatruiyehgadid 2.01 Sabluiyeh 0.95 Fath Abad 1.75 F mg/L Figure 2. F level in the drinking water in the 35 villages and town in the Zarand region. 136 Research report Occurrence of fluoride in groundwater of Zarand region, Iran 136 Fluoride 47(2)133–138 Derakhshani, Tavallaie, Raoof, Mohammadi, Abbasnejad, Haghdoost April-June 2014 The F level in the drinking water had a range of 0.33–3.51 mg/L, a mean of 1.8 mg/L, a median of 1.64 mg/L, a variance of 0.69, a skewness of 0.27, and a SD of 0.83. The lowest F concentration of was observed in the Sang site (0.33 mg/L) while the maximum concentration was recorded from Motahar Abad (3.51 mg/L). In 22 of the villages and towns (63%) the F level was higher than 1.5 mg/L, the maximum level recommended by the World Health Organization (WHO)34 (Motahar Abad, Deh-Asgar, Ab-pangueyeh, Dahuiyeh, Sirize 1, Bab-Tangal, Reyhan Shahr, Shabchareh, Deh-Irag, Shahrokh Abad, Gatruiyehgadim, Hamidiyeh, Gatruiyehgadid, Yazdan Abad, Deh-Milan, Fath Abad, Deh-Shig, Madboon, Tagi Abad, Dashtkhac, Khanuk, and Hosn Abad)(Table 1, Figure 1, and Figure 2).The remaining 13 villages and towns (37%) had levels below 1.5 mg/L (Rashk Sar, Hosn, Gorgafk, Banan, Bab-Haviz, Chahkin, Badiz, Sirize, Sabluiyeh, Sarbag, Zarand, Yazdan Abad 1, and Sang)(Table 1, Figure 1, and Figure 2). 8 Mean = 1.80 The F levels in the ground SD = 0.832 Frequency N = 35 water showed a normal 6 distribution suggesting that T natural processes were involved h (Figure 3). 4 e The calcium levels of the swater were analyzed because 2 efluoride toxicity is increased lwhen calcium levels are very 0 elow (Table 2). 0 1 2 3 4 Fluoride mg/L c Figure 3. Frequency histogram of fluoride in t groundwater in the Zarand region. e Table 2 . Ca level in the drinking water in the 35 villages and towns in the Zarand region d Village or town Ca ppm Village or town Ca ppm Village or town Ca ppm r Ab-pangueyeh 58 Deh-Milan 34 Sirize 44 e Badiz 44 Gatruiyehgadim 66 Sang 38 g i Banan 74 Hosn Abad 54 Sirize1 286 o Chahkin 58 Hoosn 76 Shahrokh Abad 438 n Dasht khac 54 Hamidiyeh 34 Rashc Sar 98 Deh-Shigh 100 Madboon 90 Reyhan Shahr 102 f o Dahuiyeh 116 Gorgafk 30 Shahrokh Abad 96 r Bab-Haviz 48 Motahar Abad 60 Tagi Abad 176 Bab-Tangal 156 Deh-Irag 58 Yazdan Abad 22 t Deh-Asgar 480 Khanuk 70 Yazdan Abad 1 40 h i Shabchareh 76 Sarbag 74 Zarand 100 s Gatruiyehgadid 38 Sabluiyeh 106 Fath Abad 438 137 Research report Occurrence of fluoride in groundwater of Zarand region, Iran 137 Fluoride 47(2)133–138 Derakhshani, Tavallaie, Raoof, Mohammadi, Abbasnejad, Haghdoost April-June 2014 Groundwater is a major source of drinking water in the semi-arid Zarand region, geologically part of the so-called Central Iran Zone.